Increasing moisture along the New Mexico and Arizona border, along with an upper level disturbance, provided a focus for thunderstorm development across southeast Arizona. Some of the storms produced heavy rainfall, strong winds, and frequent lightning.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS TWC wrote it up.
Increasing moisture along the New Mexico and Arizona border, along with an upper level disturbance, provided a focus for thunderstorm development across southeast Arizona. Some of the storms produced heavy rainfall, strong winds, and frequent lightning.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Tucson, AZ wrote its last area forecast discussion before the first event at Aug 11, 10:45 AM MST, 2 hours 15 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TUCSON AZ 1045 AM MST THU AUG 11 2011 .SYNOPSIS...A WEAK MID LEVEL DISTURBANCE IN COMBINATION WITH AMPLE MOISTURE WILL BRING SCATTERED SHOWERS AND THUNDERSTORMS TO SOUTHEAST ARIZONA INTO THIS EVENING. LOCALLY HEAVY RAINFALL WILL OCCUR WITH THE STRONGER THUNDERSTORMS. THE DISTURBANCE WILL THEN MOVE NORTH OF THE AREA FRIDAY. ALTHOUGH RAINFALL CHANCES WILL LESSEN SOMEWHAT... THERE WILL STILL BE SUFFICIENT MOISTURE FOR AT LEAST A SLIGHT CHANCE OF THUNDERSTORMS MAINLY FROM TUCSON EASTWARD THIS WEEKEND AND EARLY NEXT WEEK. DAYTIME TEMPERATURES WILL REMAIN SEASONABLE. && .DISCUSSION...KEMX WSR-88D DETECTED ISOLATED 30-45 DBZ ECHOES ACROSS THE TOHONO NATION AND NEAR THE HUACHUCA MTNS. THE REST OF SE AZ WAS VOID OF PRECIP ECHOES. NO CHANGES ANTICIPATED TO THE INHERITED FORECAST AS THE 11/12Z GFS/NAM AND 11/09Z SREF WERE SIMILAR WITH REGARD TO DEPICTING THE BEST CHANCE OF MEASURABLE PRECIP TO OCCUR FROM TUCSON EWD/SWD THIS AFTERNOON AND THIS EVENING. 11/12Z KTWC SOUNDING DEPICTED AND ENVIRONMENT THAT WAS SLIGHTLY MORE MOIST AND SLIGHTLY MORE STABLE VERSUS 24 HOURS AGO. HOWEVER...STEERING FLOW HAS CHANGED TO MORE-SELY VERSUS WED MORNING. THUS...SHOWERS/TSTMS THAT DEVELOP ARE EXPECTED AT THIS TIME TO ADVANCE FURTHER NWWD INTO SOUTH-CENTRAL PINAL COUNTY AND WRN PIMA COUNTY VERSUS WED. PLEASE REFER TO THE PREVIOUS DISCUSSION SECTION FOR ADDITIONAL FORECAST DETAIL. && .PREV DISCUSSION...MODEL DATA CONTINUES TO SHOW BULK OF MOISTURE ALONG THE INTERNATIONAL BORDER AND OVER COCHISE COUNTY. SO ONCE AGAIN...EXPECTING THE INITIAL DEVELOPMENT THERE AND IN HIGHER ELEVATIONS. HOWEVER...THIS MOISTURE COUPLED WITH MID LEVEL DISTURBANCE WILL LEAD TO GREATER THUNDERSTORM COVERAGE THIS AFTERNOON AND INTO THIS EVENING...WITH POPS 40 PCT IN THE TUCSON METRO AREA. MOISTURE WILL DIMINISH THIS WEEKEND...BUT ENOUGH WILL LINGER TO KEEP POPS IN THE FORECAST...WITH BEST CHANCES AGAIN SOUTH AND EAST OF TUCSON. THIS PATTERN WILL REMAIN IN PLACE FOR THE REMAINDER OF THE FORECAST PERIOD AS UPPER LEVEL CIRCULATION REMAINS FAIRLY CONSISTENT OVER THE PERIOD. NO SIGNIFICANT CHANGES TO FORECAST...AS INHERITED FORECAST HANDLES THE ABOVE VERY WELL. && .AVIATION...ISOLD-SCT TSRA/SHRA ACROSS SE AZ THRU 18Z FRIDAY. THE BULK OF PRECIP IS EXPECTED FROM KTUS VICINITY EWD/SWD. MVFR CIGS/ VSBYS...MTNS OBSCD...AND WIND GUSTS TO 40-45 KTS WITH THE STRONGER TSRA. OTHERWISE...SCT-BKN CLOUDS WITH BASES AT 8-12K FT AGL AND SURFACE WIND MAINLY LESS THAN 10 KTS THRU FRIDAY MORNING. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...EXPECT ISOLATED TO SCATTERED MAINLY AFTERNOON AND EVENING THUNDERSTORMS INTO THE MIDDLE OF NEXT WEEK. NORMAL DIURNAL WIND TRENDS WILL OCCUR...EXCEPT STRONG AND GUSTY WINDS WILL PREVAIL NEAR THUNDERSTORMS. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. BF WEATHER.GOV/TUCSON
The Tucson radar (KEMX), 55 km away, was scanning. The volume nearest the first event began at 20:01 UTC.
1 lightning, 1 flash flood, 1 thunderstorm wind. Local standard time, as filed.
Two illegal immigrants were struck by lightning near Sierra Vista and transported to a hospital. The Border Patrol reported that the injuries sustained by the two illegal immigrants was consistent with a lightning strike.
Rainfall amounts up to 2.5 inches resulted in flash flooding in the Kino Springs area. Several washes and the Santa Cruz River flooded resulting in the closure of several local roads.
Thunderstorm wind gusts over 60 mph resulted in minor damage in Fort Thomas. Several truck trailers were blown through yards resulting in a few outbuildings being destroyed. A tool shed was also severely damaged and a few small trees were downed.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Arizona in 2011Every state in 2011This day in weather historyWarnings in Arizona, August 2011
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 344683, 340260, 340259.